Mix yeast with sugar and a little bit of warm water and leave aside to rise for 10 minutes.

Dust your hands with flour. Combine yeast mixture with flour in a larger bowl, add ⅔ cup of warm water, and start kneading the dough. Add water gradually as you are working the dough. You may find you need a little bit more or a little bit less. You want to make the dough that's elastic, and easy to stretch. Once the dough ball is made, leave to rise in a warm place for 30 minutes.

Heat oven to 480-500F. Prep your toppings by slicing up the meat and mushrooms thinly. Grate the cheese, or if unable to, tear each slice up into a few pieces.

Take the dough out of a bowl and place on a dusted working space. Roll it out until it's about 14-15 inches in diameter. Transfer onto a pizza stone or a round pan that's been dusted with flour.

Spread ketchup evenly over the pizza. Add cheese first and then the remaining toppings: meat, then mushrooms and finally kajmak. Finish with oregano.

Bake 10-12 minutes. Take out and add olives. (Add more ketchup on top if you'd like.)